Ground school
How an airplane flies
Lift from the wing, the four forces, angle of attack and the stall, and why airspeed discipline is the first habit an instructor builds.
Not flight instruction and not an approved course. A certificated flight instructor is where training happens. Find a school near you.
Start here
A wing makes lift by meeting the air at an angle and deflecting it. In steady flight the four forces balance: lift against weight, thrust against drag. Push the wing's angle to the air past its critical angle of attack and the flow separates and lift falls sharply. That is the stall, and it happens at an angle, not at a fixed airspeed.
The full treatment, with the diagram, is in the lesson how a wing works. Read that before going on.
The vocabulary you will meet
An instructor will use these on day one and a POH or listing will use them without explanation.
- Angle of attack, and the critical angle where the stall lives
- The four forces: lift, weight, thrust and drag, and how they balance in steady flight
- Load factor, and why a steep turn raises the speed at which the wing stalls
- V-speeds, and why the numbers are in your POH and not here
Check yourself
The knowledge quiz draws from this material. Every answer links back to the page it came from, so a wrong answer is a link to the explanation rather than just a cross.